Car startes when it wants to. It has power to lights and all gages but when I turn the key it does nothing. New motor. Any suggestions?

Could be a bad starter or just a bad ground. check or replace all the ground wires first. I've had alot of problems that I was told would cost me hundreds and turned out to be a corroded ground connection. So disconnect them even if they don't look bad, then at least clean the metal with a wire brush. It will save you headaches in the future.

fuseable link on starter main bolt [red heavy wire link attached to it]